A very worthwhile collection that includes pieces well known, and crucial to the form - though probably already in the collections of students and specialists -: Corale, ╬Weekend', Etude Violette, Scambi, Poeme Electronique, Concret PH, Rozart Mix, Aspekt, plus a number of unreleased pieces, mostly of interest though not always great, of which for me the most resonant is one by Sonic Youth, made at the end of a concert, where they turned their microphones onto a baying crowd and processed the sound they made in real time. A gem. This is a fine collection for those wanting some grounding in the history of electronic music and for those who will want some of these unreleased pieces. The presentation is eccentric, not chronological, with Pousseur and Mumma in the chronology section and Varese and Cage in the ╬exploration' section, which is not organised chronologically, nor in any other way that I can perceive. There are notes, but they don't explain the raison d'etre of the order or the choice of pieces either. Better to ignore the educational or historical part and take this as an almost random scattering of interesting pieces by participants in the unfolding story of electronic music. There are rarities here, and strange unexplained juxtapositions. A ╬ postmodern' approach one might say; slightly scattershot with no clear intellectual underpinning. Are Varese, Cage and Fennesz really comparable in a coherent way?The bulk of the music, however, can speak for itself.